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Bimetallic catalysts NiCo/CNTs with distribution-controlled Ni and Co species were prepared by modified impregnation method with the assistance of dimethylbenzene and characterized by XRD, N2 adsor...

A novel chemiluminescence (CL) method to determine putrescine was proposed based on the enhanced effect of putrescine on CL emission of the [Ag(HIO6)2]5−–luminol system. The enhanced degree of CL emission was proportional to the putrescine concentration. Under optimal conditions, there was a linear relationship between the increase in CL intensity and the putrescine concentration over a range of 4.0 × 10−8 to 4 × 10−6 g mL with a detection limit (3σ) of 1.76 × 10−8 g mL−1. The relative standard deviation (RSD) was 3.2% for 11 replicate determinations of 1.0 × 10−6 g mL−1 putrescine. The proposed CL reaction systems had potential capability for residue analysis of studied analytes in food samples. A possible mechanism of CL emission and enhanced effect was also suggested.

In the microbial fermentation bioreactor, the processes of mRNA transcription, protein translation, and enzyme-catalyzed biosynthesis remain as “black boxes” of industrial monitoring and process control. Monitoring the kinetics of these “black boxes” is very helpful for optimizing and controlling the microbial fermentation process. This study first applied a molecular beacon (MB) to monitor the changes in the mRNA level of the phzC gene during antibiotic phenazine-1-carboxylic acid fermentation. Seven typical MB hybridization buffers were compared, and the effect of formamide on MBs was also studied. The results showed that rapid monitoring of the mRNA level using MBs was feasible. The optimal hybridization buffer for phzC MB was 100 mM Tris, 1 mM MgCl2, pH 8.0. The optimal hybridization temperature was 35 °C, and formamide proved unsuitable for MB hybridization. The limit of detection of phzC MB was 1.67 nM and MB hybridization was complete by 7 min. Given that the time for RNA extraction is 12 min, it is possible that monitoring of phzC mRNA can be completed in less than 20 min. Since production of most amine acids, organic acids, wines, antibiotics, and proteins relies on microbial fermentation, our method may have some potential for application in these other microbial industries.

Replication and assembly of viruses from the family Reoviridae are thought to take place in discrete cytoplasmic inclusion bodies, commonly called viral factories or viroplasms. Rice black streaked dwarf virus (RBSDV) P9-1, a non-structural protein, has been confirmed to accumulate in these intracellular viroplasms in infected plants and insects. However, little is known about its exact function. In this study, P9-1 of RBSDV-Baoding was expressed in Escherichia coli as a His-tagged fusion protein and analysed using biochemical and biophysical techniques. Mass spectrometry and circular dichroism spectroscopy studies showed that P9-1 was a thermostable, α-helical protein with a molecular mass of 41.804 kDa. A combination of gel-filtration chromatography, chemical cross-linking and a yeast two-hybrid assay was used to demonstrate that P9-1 had the intrinsic ability to self-interact and form homodimers in vitro and in vivo. Furthermore, when transiently expressed in Arabidopsis protoplasts, P9-1 formed large, discrete viroplasm-like structures in the absence of infection or other RBSDV proteins. Taken together, these results suggest that P9-1 is the minimal viral component required for viroplasm formation and that it plays an important role in the early stages of the virus life cycle by forming intracellular viroplasms that serve as the sites of virus replication and assembly.

To find new strobilurin analogues with high activity against resistant pathogens, a series of (E)-α-(methoxyimino)benzeneacetate derivatives containing 1,2,4-triazole Schiff base side chain were designed and synthesized. Their structures were confirmed by IR,1H NMR, and13C NMR, ESI-HRMS, or elemental analyses. Bioassays indicated that most of the target compounds showed moderate to good fungicidal activities againstRhizoctonia solani,Botrytis cinerea Pers.,Fusarium graminearum,Cotton rhizoctoniosis, andBlumeria graminis. For example, compounds6gand6jexhibited promising antifungal activity againstRhizoctonia solani,Botrytis cinerea Pers.,andFusarium graminearum. Compounds6c,6l, and6mhad higher fungicidal activities againstBlumeria graminisat the concentration of 50 µg/mL; inhibitory rate is 91.41%, 92.13%, and 91.77%, respectively.

A sensitive and reliable high performance liquid chromatograph-fluorescence detection (HPLC-FLD) method for the determination of diethylstilbestrol (DES) in human urine is developed. DES was derivatized with 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride (DIB-Cl) under mild conditions and separated isocratically on a C18 column. The detection limits of DES at a signal-to-noise ratio (S/N) of 3 was 0.5 ng ml−1, and the recoveries for the addition of different concentrations of DES to samples were in the range of 78.5–88.3% with RSD (n = 5) of less than 6.4%. The method was successfully applied to the determination of DES in human urine samples.